1. Field of the Invention
The present invention relates to a film deposition method.
2. Description of the Related Art
Conventionally, as described in Japanese Laid-Open Patent Application Publication No. 2015-165549, a substrate processing method is known that includes steps of causing a silicon-containing gas to adsorb on a surface of a substrate provided in a process chamber by supplying the silicon-containing gas to the substrate, performing a first plasma process on the substrate on which the silicon-containing gas is adsorbed by using first plasma generated from a first plasma processing gas containing hydrogen, and performing a second plasma process by using second plasma generated from a second plasma processing gas that does not contain hydrogen gas but contains ammonia gas on the substrate on which the first plasma process has been performed.
In such a film deposition method as described in Japanese Laid-Open Patent Application Publication No. 2015-165549, by performing the second plasma process using the second plasma having high ion energy and high radical concentration on the substrate after performing the first plasma process using the first plasma having low ion energy and low radical concentration, generation of a loading effect can be prevented, and a SiN film having excellent uniformity across the surface of the substrate can be deposited on the surface of the substrate.
However, in recent years, film deposition processes for filling a recessed pattern having a high aspect ratio such as a trench and a via hole with a film, are often required. Thus, film deposition processes for filling the recessed pattern having the high aspect ratio with the film with preferable bottom-up characteristics are widely required separately from the film deposition process conforming to the recessed pattern with the preferable uniformity across the surface of the substrate. In other words, when filling the recessed pattern having the high aspect ratio, if the film fills an upper portion of the recessed pattern more than the bottom portion of the recessed pattern and thereby blocks the upper portion of the recessed pattern, a void is liable to be generated in the film filling the recessed pattern. Accordingly, a film deposition method for gradually filling the recessed pattern with a film from the bottom portion without blocking the opening is required.